An electrical connecting apparatus is provided with a plurality of contacts, brings the front end (tip) of each contact into contact with an electrode of an electronic device, and passes a current through the electronic device, thereby receiving an electrical signal from the electronic device and transferring the signal to a tester connected with the apparatus to conduct a test of electrical property.
Usually, multiple contacts are arranged in the electrical connecting apparatus in one or more rows to correspond to the arrangement of the electrodes of the electronic device to be tested.
In such a row or rows of the contacts, when one contact becomes unusable or unsuitable for use due to breakage, wear or the like, even if the other contacts of the same row is sufficiently usable, it becomes impossible to test of the electronic device by using the row. If there are many unusable contacts, it can be taken into consideration to replace the electrical connecting apparatus itself, but if there are only a few, it is economical to replace only such contacts.
In Patent Documents 1-3 are described such methods of replacing unusable contacts.
The method of replacing as described in Patent Document 1 is carried out in such a manner as, after cutting and removing a probe which became unusable, a replaceable probe is newly attached to a fixing region set on the electric wiring of a wiring board.
According to this method of replacing, however, the narrower a pitch between the probes is, the harder the replacing work becomes.
The replacing method according to Patent Document 2 is carried out by forming a block (probe card sub-base plate at each of the probes) and replacing the block to which the unusable probes belong.
There is a problem in this method, however, that a work for adjusting a pitch between a newly replaced block and the other blocks is necessitated, which is troublesome and inconvenient. In addition, there is another problem that it also takes time and labor in positioning to remount a probe card which had been dismounted from a probe card assembling apparatus for the replacement work.
The replacing method described in Patent Document 3 is carried out by replacing a needle having bad conductivity with a spare needle.
This replacing method, however, is meant to be applied to an integrated circuit chip to be tested which is provided with spare electrodes, so that it is not suitable for ordinary integrated circuit chips which have no spare electrodes.
Further, as a prior art of an electrical connecting apparatus provided with contacts and their spare contacts, Patent Document 4 describes one which uses a spare probe when a probe becomes unusable. The probe card described in Patent Document 4 comprises probes and spare probes juxtaposed thereto.
However, since the spare probes of this probe card is juxtaposed to the probes which become unusable and arranged in the same probe rows, if a pitch between the probes and the spare probes is narrow, it is difficult to use the spare probe alternatively for the probe which became unusable.    Patent Document 1: JP Patent Appln. Public Disclosure No. 2007-107937    Patent Document 2: JP Patent Appln. Public Disclosure No. 6-349904    Patent Document 3: JP Patent Appln. Public Disclosure No. 7-245330    Patent Document 4: JP Patent Appln. Public Disclosure No. 6-294817